Bearing alloy



Jan. 28 1.930.

J. V; o. PALM ET AL BEARING ALLOY Filed Aug. 4, 1927 I A ma m W a WM Md 8 .w 3

' as 'with ordinary babbitts.

- Patented Jan. 28,1930

f UNITED-STATES PATENT OFFICE JOHN V. O. PALM AND EDWARD C. KNUTH, OF CLEVELAND, OHIO, ASSIGNORS TO THE CLEVELAND GRAPHITE BRONZE COMPANY, OF CLEVELAND, OHIO, A CORIPORATIQN OF OHIO BEARING ALLOY Application filed August 4, 1927. Serial No. 210,537.

The present-invention, relating, as indicated, to bearing alloys, is particularly directed to an improved metallic composition,

one particular use for which'is as a substitute 5 for the ordinary Babbitt metal. One of the principal objects of the invention is the provision of a metallic composition for the purpose indicated which shall have improved physical properties at high temperatures and 10 which shall be less expensive than Babbitt metals of ordinary composition.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the following description setting forth in detail one product exemplifying our invention, such disclosed product constituting,

however, but one of various applications of the principles of ourinvention.

In said annexed drawing The single figure there appearing is a sectional view showing upon anenlarged scale the appearance of our alloy in a photograph. 5 Uur improved alloy has as a base lead in a predominant amount, with lesser amounts of other metals, such as cadmium, zinc and antimony. Zinc is soluble in lead only very slightly, but it alloys with cadmium and antimony in any proportions and by the use of cadmium and antimony the crystals of zinc and cadmium and zinc and antimony are formed which may be observed in the matrix, which consists of cadmium, antimony and lead.

In the single figure appearing in the drawing the predominating black matrix is a combination of lead, cadmium and antimony,

while the long,*narrow crystals are formed of zinc and cadmium, and some of zinc, cadmium and antimony. The smaller and more regular or square-crystals are cubical crystals of cadmium and antimony and the fine grain and uniform distribution of the various crystals is very evident from the view referred; The crystal size in the grain structure can be varied by the rateof cooling, just We have, found that an allo of lead cadmium, zinc and antimony, in t e proportions of approximately 67 per cent of lead, 18 per cent of cadmium, 5 per cent of zinc and 10 per cent of antimony has extremely good physical characteristics for a bearing metal and retains these characteristics at high tem peratures better and to a greater degree than any other babbitt or similar metal that is now known. This alloy has approximately the same hardness as ordinary babbitt at room temperatures, but at elevated temperatures it is materially harderthan the ordinary babbitt. The approximate hardness of the two metals at 250 Fahr. may be indicated as for babbitt and 47 for the present alloy, these figures representing merely a relationship between the two. It is entirely possible by proper methods to secure an extremely close bondbetween the present composition and I steel-backed bearings of the present material. 1 Certain other properties of prime importance in a bearing metal in which our present composition is markedl superior to ordinary babbitts, are its elasticity l1m1t, and

modulus of elasticity in compression, its resistance to impact, its qualities as a bearing under restricted lubrication, and its coefficient of friction. The most marked diflen ence in these properties is found in the modulus of elasticity, which is for the presentcomposition two-thirds of that'of the prdmary babbitt, and in the coefficient of frlct-lon of the two materials. Under identical conditions the friction of the present composition is less than-two-thirds that of ordinary babbitt.

The properties of the alloy may be varied somewhat while still maintaining the desirable physical characteristics. Thus, for example, the cadmium content of the alloy may range from as low as 5 per cent to as high as 25 or 30 per cent, while the zinc can be increased to more than 10 per cent, although the effect of increasing the zinc is to pull the antimony out of the lead. The result of this vaction is .to make-it possible to increase the zinc and antimony content without increasing the hardness of the alloy. An increase in the cadmium or antimony, or both, in the matrix, and a corresponding decrease in the lead W111 .J

cause the alloy to become harder, particularly at elevated temperatures.

The present alloy is the only lead base babbitt which has been found satisfactory at high temperatures b v virtue of better retaining its hardness, an this property of the alloy is due to the presence of the cadmium and antimony in the matrix composition. The alloy may be readily mixed and formed and is materially less expensive than any of the high grade babbitts which are in general use, while its properties exceed those of all other babbitts at high temperatures.

Other modes of applying the principle of our invention may be employed instead of the one explainedmhange being made as regards the composition herein disclosed, provided the ingredients stated by any of the following claims or the equivalent of such stated ingredients be employed.

We therefore particularly point out and distinctly claim as our invention 1. A hearing alloy consisting of approximately 67 per cent lead, 15 to 18 per cent of cadmium, 5 to 10 per cent of zinc, and 6 to 15 per cent of antimony.

2. A bearing alloy consisting of approximately 67 per cent lead, 18 per cent cadmium; 5 per cent zinc and 10 per cent antimony.

Signed by us,

- JOHN V. PALM.

EDWARD O. KNUTH.

this 26th da of July, 1921 

